if you don't want later imperial vessels, then go with Order 65 and side with Mon Mothma, so you can keep your jedi, and you won't gain access to the Tector, Secutor, and Imperial through the KDY contracts.
Though you'll still get access to the VSD through research, same as you'll get access to the Venator and Phase 2 clones, because the Victory was a vessel used during the late stages of the clone wars.

Moreso that we have Victories available to research at the start of era 3 because it's a legends mod, and the majority of legends sources treat them as early-mid war. Generally before P2 clone armor is a thing going by MMP stuff.

There are sources for late war, but there's also literally more sources that have them be pre-Venator...


65/66 stay in the bar if you don't choose. There's no time limit or requirements, and you can put them off as long as you want.
Era progression occurs in the progressive GC's regardless still, and that's where things like Venator/Victory-I research or direct unlocks like AT-AP's and Acclamator-II's come from